Mapping Mountains – Significant Name Changes – 200m Twmpau

 

Sixteen Acres (SO 120 987) 

There has been a Significant Name Change to a hill that is listed in the 200m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

Sixteen Acres (SO 120 987)

The criteria for the list that this name change applies to are: 

200m Twmpau - Welsh hills at or above 200m and below 300m in height with 30m minimum drop, with an accompanying sub list entitled the 200m Sub-Twmpau with the criteria for this sub category being all Welsh hills at or above 200m and below 300m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

The 200m Twmpau by Myrddyn Phillips

The hill is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with the B4390 road to its north, the B4389 road to its west and the A483 road further to its south-east, and has the village of Tregynon towards the west. 

When the original 200m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website this hill was not included in the accompanying Hills to be surveyed sub list, as it was considered not to meet the criteria then used for this sub category.  

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-assessed and it was listed under the point (Pt. c 216m) notation with an estimated c 20m of drop, based on an estimated c 216m summit height and the 196m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was named the Interactive Coverage Map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

When visiting this hill I met Paul Marsh on the lane leading toward it.  Paul rents the land where the summit of this hill is situated and told me that he had never heard an individual name for the hill, and although he knew the uppermost field as Coed y Perthi or Alan’s Land, he advised me to call at the red bricked house further up the lane as Alan Jones who owns the land would no doubt know the proper field name. 

Paul Marsh

The two names Paul gave me relate to the house between where I met Paul and Alan Jones’s house, this is marked by the same name on Ordnance Survey 1:25,000 maps; Coed y Perthi.  The second name relates to the person who owns the land; Alan’s Land. 

Thanking Paul I asked permission to visit the hill, which was duly granted, and continued up the lane and after surveying the summit, called at Alan Jones’s house.  He was out, but his son; Ryan was extremely helpful.  I explained my interest in place-names and as we were standing outside I pointed toward the top of the field that I had just visited and surveyed.  Ryan told me that the field where the summit of this hill is situated is known as Sixteen Acres. 

Ryan Jones

Therefore, the name this hill is now listed by in the 200m Twmpau is Sixteen Acres, and this was derived from local enquiry.

 

The full details for the hill are:

Group:  Carnedd Wen

Name:  Sixteen Acres

Previously Listed Name:  Pt. c 216m   

OS 1:50,000 map:  136

Summit Height:  219.2m (converted to OSGM15, Trimble GeoXH 6000) 

Summit Grid Reference:  SO 12005 98756 (Trimble GeoXH 6000) 

Bwlch Height:  199.1m (LIDAR) 

Bwlch Grid Reference:  SO 19953 98547 (LIDAR) 

Drop:  20.1m (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

Myrddyn Phillips (January 2021)